This paper presents the findings of a study that examined pre-service teachers' development of knowledge about technology, pedagogy and content (TPACK) during a mathematics pedagogy course focused on elementary school mathematics in the United States. Data sources included work samples from pre-service teachers as well as an open-ended survey collected at the end of the semester. Inductive analysis of the data indicated that pre-service teachers demonstrated varying levels of technological knowledge, but all demonstrated greater gains in their knowledge of mathematics content and pedagogical content knowledge. Implications for the design of pre-service mathematics education courses focused on elementary school mathematics are also shared.